1. Field of the Invention
The present invention relates to a landing deck for aircraft, and in particular, but not exclusively, to a helicopter deck of the type used on seagoing vessels and installations, such as offshore platforms.
2. The Prior Art
It is desirable to protect such decks against fire. There is always a danger of accidents and damage, to a larger extent than on airfields, because of adverse weather conditions and because the deck follows the movements of the vessel or platform. In an accident fuel from a helicopter may leak out and to be spread along the deck, and the fuel may be set on fire. The ignition may lead to a serious fire, and the combustion intensity may be very high when the fuel is spread out on a relatively smooth surface, because the fuel presents a large surface to the air. It is of course desirable to limit and to stop such a fire as soon as possible, and it is known to provide systems adapted to coat the deck with foam in order to stop the fire. It is of course also known to place extinguishing equipment, such as foam extinguishers, on or near the decks, and, moreover, it is known to provide channels in the runways of airfields, for spraying of foam. In Norwegian Acceptance Print No. 139.526 is described means adapted to coat a helicopter deck with foam in order to stop a fire, whereby a framework is placed above a planar deck and a lattice work above the framework. In the cavities thereby formed below the lattice work are provided apertures for spraying of foam. The purpose of this is among else to prevent that the foam being sprayed is blown away without giving any fire-extinguishing effect.
Thus, the known systems first of all concern means for extinguishing a fuel fire which has been spread along a deck.